Gustav fischer



(N0 Model.)

G. FISCHER. THERMOSTAT AND ALARM. No. 485,789. i Patented Nov. 8, 1892.

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GUSTAV FISCHER, OF CHEMNITZ, ASSIGNOR TO ARNO VIEWEG, CF SIEGMA'R,GERMANY.

THERMOSTAT AND ALARM.

SPECIFICATION forming part of Letters Patent No. 485,739, dated November8, 1892.

Application filed July 20, 1892. Serial No. 440,617. (No model.)

.To @ZZ whom it may concern:

Be it known that I, GUSTAV FISCHER, of Chemnitz, in the Kingdom ofSaxony, German Empire, have invented certain new and usefullmprovementsin Thermostats and Alarms,

of which the following is a specification.

This invention is in the nature of an electrical indicator intendedfor'use especially as a hand-alarm or push-button bell and a irealarm tosound upon the rise of the temperature of the surrounding atmosphere,but which can be applied to any of the well-known uses to which electricalarms are put.

It consists in the improved construction, arrangement, and combinationof parts hereinafter fully described,and afterward specifically pointedout in the claims.

In the accompanying drawings, Figure l is a top plan View; Fig. 2, acentral vertical section on the line a a', Fig. l; Fig. 3, an elevationof the alarm-bell, and Fig. 4. a view of the battery. Dotted linesbetween Figs. 1, 3, anda and connecting therewith show theli nes of theconnecting-wires to form the circuits.

Like letters of reference mark the same parts in all the figures of. thedrawings.

Referring to the drawings by letters, b is a circular block or disk ofwood or other nonconducting material.

cis a metal ring superposed thereon and having its upper face graduated.In the center of the disk b is an insulatingcup k, in which is placedthe step-bearing for the lower end of an upright shaft c', which has itsupper bearing in the underside of a metal bow or arch Z, which issecured at its outer ends by screws to the disk b. Upon this shaft isattached the inner end of a at coiled spring g, which has a lining orcoating m of hard 4o gelatine. The outer end of the spring g is attachedto a metal support h, secured by screws at its lower end to the disk b.Below the spring g a hand or finger -n is secured to shaft z', the outerend of which reaches over the gradu- 45 ated ring c. Another hand ornger d is mounted around the insulated socket or cup 7c, the outer endof which hand rests upon the top of the graduated ring c and can berigidly fixed at any point thereon by means of a pin o, which serves asa contact to limit the mo- 5o tion of hand n, before described.

u is a metal spring secured at its lower end to the disk b by screw orotherwise,havingits upper end above the arch l and carrying apush-button t of any ordinary shape Vor material.

Freni the battery or other source of electricity, Fig.4:,the circuitisas follows: Through Wire q to binding-post p and thence by wire ftofinger d, fixed,as before stated,at a given 6o point on ring c, andthrough wire r to bells, thence to binding-post s, thence to metalsupport h, to spring g, shaft fi, and finger n. To

complete this circuit and cause the bell to ring, the finger n must bebrought into contact with stop-pin o onfinger d. This is effectedwhenever the coating of gelatine m on spring g is softened by the riseof the temperature of the surrounding atmosphere in case of the start ofa coniagratiomthe gelatine in its 7o hard state serving always toprevent the spring from moving. When the gelatine is on the outside ofthe spring, it will keep it from winding up, and when inside fromunwinding.

Another circuit runs from the source of electric energy, as the battery,Fig. 4, through Wire q, binding-post p, and spring u to pushbutton t;also, from battery through wire r and the bells, Fig. 3, to post s andthrough wire r to arch Z. This circuit is completed and 8o the alarmsounded by hand by pressing the push-button 1f until spring u comes incontact With the arch l.

The operating mechanism may be protected by a cover fn, which should beperforated to permit the changes in the temperature of the atmosphere toreadily affect the gelatine.

Having thus fully described the invention, What is claimed as new, anddesired to be secured by Letters Patent of the United States, 9o 1sl. Ina irealarm,a flat spring held against its normal tendencyin astrainedposition by a hard coating or sheet of gelatine thereon, as set forth.

2. The combination, with a source of electric energy and an alarm,of aspring connected to and in circuit therewith, coated with hard gelatineto hold the spring in position ure the battery, bells, and arch l, incombina.- to maintain the circuit open, as set forth. tion with thepush-button t and spring fu), as

3. In combination, the spring coated with sei; forth. gelatine, meansfor holding its outer end, the In witness whereof I have hereunto signed15 5 post to which its inner end is secured, the xmy name in thepresence of two subscribing y ing-linger with stop-pin, and the movingfinwitnesses. gersecured to the post or shaft and arranged to be stoppedby the stop-pin when the spring is released by the softening of thegelatine, IVitnesses: Io as set forth. R. E. JAHN, l

4. The fire-alarm comprising in its Structl EUGEN A. FRAISSINET.

eUsTAV FisoHER.

